One of my brothers ran cross-country in high school, which enabled him to eat three two-packs of peanut butter cups daily. How I envied him! But recently, my older son and I, looking for an idea for his birthday cake, spotted a recipe for “Peanut Butter Cup" in Icebox Cakes, a ravishing new cookbook. What luck! I’d get to indulge my sweet/salty tooth while treating his party guests.
The birthday fell at the end of an insanely busy week, so I assembled and froze the cake a week ahead. The day before his party, I transferred it to the fridge, then, frosted it with whipped cream right before serving. At the sleepover, the air was filled with the groaning of happy but bloated preteen boys. So when they asked for more the next day, I’d learned my lesson: cut smaller slices.
Full disclosure: Icebox Cakes is by Jesse Sheehan, my husband’s old girlfriend. She’s a lovely, generous, meticulous dynamo who doesn’t look like she's ever eaten a cake in her life. But I adore Jesse, and her book is a bonanza of confections inspired by the classic made of Nabisco Famous Wafers and whipped cream. Her cakes run the gamut from lavender-blueberry to black and white malted. Because she’s a high achiever, she includes recipes for homemade wafers in flavors from chocolate to pistachio. However, I used store-bought graham crackers in mine, and you can too. It’ll still be dreamy.
Peanut Butter Cup
adapted from Icebox Cakes by Jesse Sheehan; more details at jessiesheehanbakes.com
Make Peanut Butter Pudding
(You could stop here, serve it to your loved ones, and rest on your laurels.)
1 1/3 cups/265 grams granulated sugar
6 tbsp/50 g cornstarch
1 tsp salt
3 1/2 cups whole milk
1 cup heavy cream
2 eggs, lightly beaten
3/4 cup/195 g creamy peanut butter, at room temperature
2 tbsp unsalted butter, at room temperature
1 tbsp vanilla extract
Whisk together sugar, cornstarch, and salt in a large saucepan. Add the milk and cream and whisk to combine. Add eggs and whisk again, then place pan over medium-high heat, whisking constantly. When the mixture begins to thicken and bubbles start to pop on the surface, reduce heat to medium and whisk for 45 seconds. Remove pan from heat and strain the pudding through a mesh strainer into a heatproof bowl. Whisk in peanut butter, butter, and vanilla. Use it while it’s still warm and pourable.
Make Milk Chocolate Ganache
13 oz/370 g milk chocolate, finely chopped
1∕4 tsp salt
3∕4 cup heavy cream
Place the chocolate and salt in a medium heatproof bowl and set aside. In a heatproof measuring cup, microwave the cream at medium power till bubbles form around the edges, 30 seconds at a time. Pour the warm cream over the chocolate and salt. After a minute whisk together until fully incorporated and shiny. Let come to room temperature, stirring occasionally, until it thickens.
Assemble the Cake
(you’ll need a box of graham crackers)
Lightly coat the inside of a springform pan with cooking spray. If you’re going to freeze the cake, line the bottom of the pan with a sheet of plastic wrap. Line the sides of the pan with a 3” x 29” strip of baking parchment (easier than it sounds). Spread a layer of pudding on the bottom of the pan. Cover the pudding with a layer of graham crackers. I broke the crackers into pieces to fill in gaps. Coat this layer with ganache. Repeat layers (pudding, crackers, ganache) till you run out or reach the top of the pan. Gently cover with plastic wrap, put the cake on a plate, and refrigerate for 24 hours.
***If you plan to freeze the cake, leave it in the fridge for 24 hours, then run a knife around it and remove sides, but not bottom, from the pan. Set it gently in the freezer to solidify for a day, then remove it from the pan bottom and swathe the whole thing carefully in plastic wrap. Before serving, unwrap and thaw the cake on a serving plate in the fridge for a day. Frost before serving.***
Make Peanut Butter Whipped Cream
(Make the whipped cream shortly before serving)
2 cups heavy cream
1/3 cup/85 g creamy peanut butter, at room temperature
1/4 cup/35 g confectioner’s sugar
1 tsp vanilla extract
Whip cream in chilled bowl till just thickened. Be careful not to go beyond this to the soft-peaks stage. Add peanut butter, confectioner’s sugar, and vanilla. At medium-high speed, whip till it holds stiff peaks. Use immediately.
Spread top and sides with whipped cream and stud the top with chopped peanut butter cups.